JP2017049279A - Toner conveyance device, toner supply device and image formation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent toner clogging by maintaining the amplitude of the vertical motion in a toner conveyance device in which a toner conveyance member performs the vertical motion by a non-circular rotary body and a coil spring.SOLUTION: A toner conveyance device 40 includes: a toner conveyance member 41 which is arranged so that openings on both ends of a toner conveyance path face upward and downward; a support member 42 which supports the toner conveyance member 41 so as to be movable in the vertical direction; and a drive mechanism which causes the toner conveyance member 41 to vertically move with respect to the support member 42 by a non-circular rotary body 31 which can contact a protrusion part 41a provided on the upper side of the toner conveyance member 41 and a coil spring 43 arranged between the support member 42 and the toner conveyance member 41. The coil spring 43 is provided so that the telescopic motion direction faces the direction having a prescribed angle θ with respect to the vertical direction. The angle θ is such an angle that the upper side of the coil spring 43 is inclined in the direction of normal rotation on the protrusion part 41a side in the non-circular rotary body 31 with respect to the lower side.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a toner conveying device, and a toner supply device and an image forming apparatus including the toner conveying device.

  2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as single-function printers, facsimile machines, and multifunction peripherals (MFPs) have been distributed. This image forming apparatus forms an electrostatic latent image on the surface of a photoconductor, develops the electrostatic latent image with toner supplied from a developing device, and transfers the obtained toner image onto a sheet such as paper and fixes it. I am letting. Toner is supplied from the toner cartridge to the developing device via the toner conveying device. In the configuration in which the toner cartridge is provided above the developing device, the toner transport device has a toner transport path extending in the vertical direction.

  On the other hand, in recent image forming apparatuses, image quality has been improved, and accordingly, the particle size of toner has been reduced. The fine toner generally has poor fluidity, and the toner is likely to stay and solidify in the toner conveyance path of the toner conveyance device. Therefore, a device for solving such a problem is required in the toner conveying device.

  Japanese Patent Application Laid-Open No. 2004-228561 discloses a toner transport device including a toner transport pipe, a rotation support member that rotatably supports the toner transport pipe, and a rotation driving unit that rotates the toner transport pipe. Japanese Patent Application Laid-Open No. 2003-228561 discloses a toner transport device including a toner transport path and a toner transport path deforming unit that elastically deforms the toner transport path of an elastic member adjacent to the toner transport path.

  Japanese Patent Application Laid-Open No. 2004-228561 has a toner conveyance path through which toner is conveyed, and a toner conveyance member disposed so that the extending direction of the toner conveyance path is in the vertical direction, and the toner conveyance member in the vertical direction. There is disclosed a toner transport device including a support member that is movably supported, a drive mechanism that moves the toner transport member in the vertical direction, and an excitation mechanism that applies vibration to the toner transport member. In this toner conveying device, for the vertical movement of the toner conveying member, a non-circular rotating body such as a gear disposed above the toner conveying member, and a coil spring disposed between the toner conveying member and the main body of the support member, It has. The coil spring is attached so that its expansion / contraction direction is straight in the vertical movement direction of the toner conveying member.

JP 2008-197470 A JP 2008-96914 A JP 2008-39937 A

  However, in the technique described in Patent Document 3, the non-circular rotating body is rotated by receiving the rotational driving force of the agitating / conveying member that conveys the toner in the toner cartridge while agitating, and normally rotates in the normal direction. However, there is a case where it is necessary to reversely rotate the toner in the initial stage of toner supply. When the toner cartridge is rotated in the reverse direction, the toner conveying member moves in the horizontal direction, and the toner conveying member may not return to the original horizontal position. Vibration) and the toner conveying member may become clogged.

Even if the mechanism does not rotate the rotating body in the reverse direction, when the play is caused in the horizontal direction between the toner conveying member and the support member, the operation in which the toner conveying member escapes in the horizontal direction in the same manner. As a result, similar problems may arise.
These problems will be described later with reference to the drawings.

  The present invention has been made in view of the above-described actual situation, and an object of the present invention is to reduce the amplitude of the vertical movement in a toner conveying apparatus that moves the toner conveying member up and down by a non-circular rotating body and a coil spring. It is to maintain and prevent toner clogging.

  In order to solve the above-described problems, a first technical means of the present invention has a toner conveyance path through which toner is conveyed, and openings at both ends of the toner conveyance path are directed upward and downward. A toner conveying device having a toner conveying member arranged in such a manner as to be able to contact a support member that supports the toner conveying member so as to be movable in the vertical direction and a protrusion provided on the upper portion of the toner conveying member. A non-circular rotating body, and a drive mechanism that moves the toner conveying member in the vertical direction with respect to the supporting member by a coil spring disposed between the supporting member and the toner conveying member. The coil spring is provided such that the expansion / contraction direction is oriented in a direction with a predetermined angle with respect to the vertical direction, and the predetermined angle is such that the upper side of the coil spring is lower than the non-circular shape. Characterized in that the rotary body is an angle inclined in the normal rotation direction in the protruding portion.

  According to a second technical means, in the first technical means, the non-circular rotating body is capable of rotating in both forward and reverse directions, and the drive mechanism is configured such that the toner conveying member is rotated during normal rotation of the non-circular rotating body. Is a mechanism that pushes the toner conveying member in the horizontal direction during reverse rotation.

  According to a third technical means, in the first or second technical means, the support member includes a deformable elastic member having a toner passage at a connection portion between the opening portions at both ends of the toner conveying member. It is characterized by that.

  A fourth technical means is the first technical means according to any one of the first to third technical means, wherein the toner conveying member is located on the outer peripheral side and in the vicinity of the center in the vertical direction during the movement of the toner conveying member by the driving mechanism. It has the convex part with the front-end | tip for contacting with the inner wall of a supporting member, It is characterized by the above-mentioned.

  A fifth technical means includes a toner conveying device according to any one of the first to fourth technical means, a toner replenishing device mounted above the toner conveying device, and a lower portion of the toner conveying device, And a developing device that receives toner from the toner replenishing device via the toner conveying device.

  A sixth technical means is an image forming apparatus provided with the toner supply device in the fifth technical means.

  According to the present invention, in a toner conveying apparatus that moves a toner conveying member up and down by a non-circular rotating body and a coil spring, when the non-circular rotating body needs to be rotated in the reverse direction, the vertical movement is also performed. Thus, toner clogging can be prevented.

1 is a schematic cross-sectional view illustrating a configuration example of an image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a perspective view illustrating a configuration example of the toner conveyance device according to the first exemplary embodiment of the present invention, and illustrates a state in which the toner conveyance device is connected to a toner cartridge. FIG. 10 is a schematic diagram illustrating a conventional toner conveying device. FIG. 3B is a schematic view showing a state in which the toner cartridge driving member is rotated in the forward direction in the toner conveyance device of FIG. FIG. 3B is a schematic diagram illustrating a state where the toner cartridge driving member is further rotated in the forward direction in the toner conveyance device of FIG. 3B. FIG. 3B is a schematic diagram illustrating a state in which the toner cartridge driving member rotates in the reverse direction in the toner conveyance device of FIG. 3A. FIG. 3 is a perspective view of the toner conveying device in FIG. 2. FIG. 4 is a perspective view of the toner conveying device in FIG. 2, viewed from the opposite direction to FIG. 4A. FIG. 4 is an exploded view of the toner conveying device of FIGS. 4A and 4B. FIG. 3 is a diagram illustrating details of the toner conveyance device in FIG. 2. FIG. 6 is a schematic diagram illustrating a configuration example of a toner conveying device according to a second embodiment of the present invention.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. First, based on FIG. 1, an image forming apparatus (digital multi-function peripheral) capable of mounting the toner conveying apparatus according to the present embodiment will be exemplified. FIG. 1 is a schematic cross-sectional view illustrating a configuration example of an image forming apparatus according to the present embodiment. The image forming apparatus is not limited to the illustrated one, but includes a single-function printing apparatus, facsimile apparatus, single-function copying machine, and document reading function, copy function, print function, facsimile (FAX) in a scanner apparatus, for example. ) Multifunction machines with multiple functions such as functions.

  The image forming apparatus A illustrated in FIG. 1 forms a full-color or monochrome image on a sheet (referred to as a sheet Pa) based on image data given from a scanner apparatus or the outside of the apparatus (for example, an information processing apparatus such as a PC). A sheet (referred to as sheet Pb) is output. Therefore, the image forming apparatus A includes an exposure unit 1, a developing device 2 (2a to 2d), a photosensitive drum 3 (3a to 3d), a cleaning unit 4 (4a to 4d), a charging roller 5 (5a to 5d), Intermediate transfer belt unit 8 including primary transfer rollers (intermediate transfer rollers 6a to 6d), paper feed cassette 10, secondary transfer roller 11, fixing unit 12, paper discharge tray 15, toner cartridges 20a to 20d, toner transport device 40a to 40d, and paper transport paths SA and SB. In FIG. 1, the conveyance paths SA and SB are indicated by alternate long and short dash lines, and the sheet is guided along the conveyance path by predetermined rollers including the conveyance rollers 17-1 to 17-8. . Note that the transport path SB is a switchback transport path used during backside printing.

  The image forming apparatus A forms an image based on image data corresponding to each hue of four colors including black (K) and subtractive mixed primary colors cyan (C), magenta (M), and yellow (Y). I do. For example, the image forming apparatus A is provided with a developing device 2a, a photosensitive drum 3a, a cleaning unit 4a, and a charging roller 5a in order to form a black image, and in order to form other three color images. A similar configuration is provided. These constituent elements are arranged in a line as shown in FIG. 1 along the moving direction of the intermediate transfer belt 7 of the intermediate transfer belt unit 8.

  The charging rollers 5a to 5d are contact-type chargers that uniformly charge the surfaces of the photosensitive drums 3a to 3d, which are image carriers, to a predetermined potential. In this embodiment, the charging roller 5 is used as a charger. However, the charger used is not limited to the charging roller 5, and for example, a fur brush, a magnetic brush, or a corona wire is used. As long as it has a sawtooth shape or an ion generator, it can be used as long as it imparts a desired charging potential to the photoreceptor.

  An exposure unit 1 that is a laser beam scanning device includes a semiconductor laser, a polygon mirror, a plurality of reflection mirrors, and the like, and is modulated based on image data corresponding to each hue of black, cyan, magenta, and yellow. Each of the laser beams is irradiated onto the surface of the corresponding photosensitive drum 3a to 3d. As a result, electrostatic latent images based on image data corresponding to the hues of black, cyan, magenta, and yellow are formed on the surfaces of the photosensitive drums 3a to 3d. Instead of the semiconductor laser, for example, a well-known write head in which EL (Electro Luminescence), LED (Light Emitting Diode) and the like are arranged in an array may be used.

  The developing devices 2a to 2d respectively supply toner to the surfaces of the photosensitive drums 3a to 3d on which the electrostatic latent images are formed, and visualize the electrostatic latent images into toner images that are developer images. Specifically, the developing devices 2a to 2d receive the toner corresponding to the hue from the supply ports of the toner cartridges 20a to 20d attached to the upper portions, respectively, and change the hue formed on the photosensitive drums 3a to 3d by the toner. The corresponding electrostatic latent image is visualized as a toner image corresponding to black, cyan, magenta, and yellow hues. The toner cartridges 20a to 20d are detachably attached to the vicinity of the upper portions of the developing devices 2a to 2d via toner conveying devices 40a to 40d, respectively, and are developers corresponding to the hues of black, cyan, magenta, and yellow. Store toner. The cleaning units 4a to 4d remove and collect toner remaining on the surfaces of the photosensitive drums 3a to 3d after development and image transfer, respectively.

  The intermediate transfer belt unit 8 disposed above the photosensitive drum 3 includes an intermediate transfer belt 7, a driving roller 7-1, an intermediate transfer belt tension mechanism 7-3, a driven roller 7-2, and a primary transfer roller. An intermediate transfer roller 6 (6a to 6d) and an intermediate transfer belt cleaning unit 9 are provided. The intermediate transfer belt 7 has a structure in which a film having a thickness of about 100 μm to 150 μm is formed in an endless manner. The intermediate transfer belt 7 is stretched between a driving roller 7-1 and a driven roller 7-2 and is shown in FIG. Such a loop-shaped movement path is formed. The outer peripheral surface of the intermediate transfer belt 7 faces the photosensitive drums 3d, 3c, 3b, and 3a, and the intermediate transfer belt 7 rotates so as to face the respective photosensitive drums 3a to 3d in this order. Intermediate transfer rollers 6a to 6d are arranged at positions facing the respective photosensitive drums 3a to 3d with the intermediate transfer belt 7 interposed therebetween. These intermediate transfer rollers 6a to 6d are rollers whose base is a metal (for example, stainless steel) shaft having a diameter of 8 to 10 mm and whose surface is covered with a conductive elastic material (for example, EPDM or urethane foam). It is. With this conductive elastic material, a high voltage can be uniformly applied to the intermediate transfer belt 7. In addition, although the roller-shaped thing is used here as a transfer electrode, a brush etc. may be sufficient.

  When forming a full-color image, the primary transfer rollers (intermediate transfer rollers 6a to 6d) are provided with toner for transferring the toner images carried on the surfaces of the photosensitive drums 3a to 3d onto the intermediate transfer belt 7. A primary transfer bias having a constant voltage of a negative polarity (-) and a reverse polarity (+) is applied. The primary transfer roller is pressed against the inner peripheral surface of the intermediate transfer belt 7 with a predetermined nip pressure. As a result, the toner images corresponding to the respective hues formed on the photosensitive drums 3 a to 3 d are transferred so as to be sequentially superimposed on the outer peripheral surface of the intermediate transfer belt 7, and the full-color toner image is transferred to the outer peripheral surface of the intermediate transfer belt 7. Is formed. When a monochrome image is formed, only the primary transfer roller disposed at a position facing the black photosensitive drum 3a is charged, and disposed at a position facing the other photosensitive drums 3b to 3d. The primary transfer roller is not charged and is separated from the intermediate transfer belt 7 by a predetermined distance by a predetermined separation / contact mechanism. As a result, only a black toner image is formed on the outer peripheral surface of the intermediate transfer belt 7.

  The toner image transferred onto the outer peripheral surface of the intermediate transfer belt 7 in this way is conveyed to a position facing the secondary transfer roller 11 by the rotation of the intermediate transfer belt 7. The secondary transfer roller 11 is pressed against the outer peripheral surface of the intermediate transfer belt 7 whose inner peripheral surface is in contact with the peripheral surface of the driving roller 7-1 at a predetermined nip pressure during image formation. In this case, one of the pair of rollers is made of a hard material such as metal, and the other is made of an elastic material such as an elastic rubber roller or a foamed resin roller.

  On the other hand, the paper Pa, which is the recording paper, is pulled out from the paper feed cassette 10 or the manual feed tray 18 one by one by the pick-up roller (paper separation roller) 16-1 or 16-2, and fed through the transport path SA. Is done. Further, the registration roller 14 temporarily holds the paper Pa that is being transported in the transport path SA. Then, the paper Pa is transferred to the transfer portion (secondary transfer roller 11 and drive roller 7-1 with the timing so that the front end position of the toner image on the intermediate transfer belt 7 is a predetermined position from the front end of the paper Pa. It has the function to convey to the clamping part between.

  When the paper Pa passes between the secondary transfer roller 11 and the intermediate transfer belt 7, a high voltage having a polarity opposite to the charging polarity of the toner is applied to the paper Pa by the secondary transfer roller 11. As a result, a full-color or monochrome toner image is transferred from the outer peripheral surface of the intermediate transfer belt 7 to the surface of the paper Pa. Of the toner adhering to the intermediate transfer belt 7, the toner remaining on the intermediate transfer belt 7 without being transferred onto the paper Pa is cleaned so as to come into sliding contact with the driven roller 7-2 in order to prevent color mixing. It is collected by the cleaning unit 9 including the blade 9-1.

  The sheet on which the toner image, which is a full-color or monochrome image, is transferred is guided to the fixing unit 12 and passes between the heating roller 12-1 and the pressure roller 12-2 constituting the fixing unit 12 to be heated and Receive pressure. The heating roller 12-1 is set to have a predetermined fixing temperature by the control unit based on a signal from a temperature detector (not shown). By the operation of the fixing unit 12, the toner image is firmly fixed on the surface of the paper. The paper Pb on which the toner image is fixed is discharged onto the paper discharge tray 15 (with the printing surface facing downward) by the transport rollers 17-2 and 17-3 which are paper discharge rollers.

  The image forming operation as described above is performed by a plurality of drive units including an electric motor, gears, and the like (not shown) and a control unit that controls these drive units, and the function of the control unit is not shown, for example. This is realized by a microcomputer that receives information such as sensors and operation input units.

Next, features of the present embodiment will be described with reference to FIGS.
First, referring to FIG. 2, a usage example of the toner conveying device will be described. FIG. 2 is a perspective view illustrating a configuration example of the toner conveyance device according to the present exemplary embodiment, and illustrates a state in which the toner conveyance device is connected to the toner cartridge.

  The toner transport device 40 illustrated in FIG. 2 has a toner cartridge (toner replenishing device) 20 containing toner mounted thereon. Further, the toner cartridge 20 is driven by a toner cartridge drive unit 30 (for example, a non-circular rotating body 31 provided), and is connected to the toner conveying device 40 through this. A developing device (not shown) is mounted below the toner conveying device 40 and receives toner replenishment from the toner cartridge 20 via the toner conveying device 40. The developing device and the toner cartridge 20 can have a conventionally known structure and function. Here, the toner conveying device 40 is described as supplying only the toner from the toner cartridge 20 to the developing device side, but the toner is mixed with the toner at a certain ratio by the toner cartridge, and the toner conveying device develops it. It is also possible to adopt a configuration in which replenishment (supply) is performed on the apparatus side.

  For example, the toner conveying device 40, the toner cartridge 20, and the developing device may be arranged in a shape that forms a U-shape. Such an arrangement is due to the fact that the intermediate transfer belt 7 moves between the toner conveying device 40a and the developing device 2a as shown in FIG. A device including the toner cartridge 20, the toner conveying device 40, and the developing device (and the toner cartridge driving unit 30) can be called a toner supply device. The toner replenishing device can be provided in an image forming apparatus such as the image forming apparatus A in FIG.

  Next, for comparison with the present embodiment, first, a conventional toner conveying device will be described with reference to FIGS. 3A to 3D. 3A is a schematic diagram illustrating a conventional toner conveying device, FIG. 3B is a schematic diagram illustrating a state in which a toner cartridge driving member is rotated in the forward direction in the toner conveying device in FIG. 3A, and FIG. 3C is a toner in the toner conveying device in FIG. FIG. 3D is a schematic diagram illustrating a state in which the cartridge driving member is further rotated in the forward direction, and FIG. 3D is a schematic diagram illustrating a state in which the toner cartridge driving member is rotated in the reverse direction in the toner conveyance device in FIG. 3A.

  A non-circular rotating body 110 similar to the non-circular rotating body 31 is a rotating body that is non-circular due to a protrusion (rib) 111 or the like, but a stirring transport member that transports the toner in the toner cartridge while stirring. Rotation is received under normal rotational driving force, and usually only forward rotation as indicated by arrows in FIGS. 3A to 3C is required. The non-circular rotating body 110 can come into contact with the protrusion 103 provided on the upper portion of the toner conveying member 102 and is arranged between the non-circular rotating body 110, the support member 101, and the toner conveying member 102. The toner conveying member 102 is moved up and down with respect to the support member 101 by the coil spring 104.

  At the time of forward rotation, first, as shown in FIG. 3A, the protrusion 111 provided on the upper portion of the toner conveying member 102 starts to be pressed by the protrusion 111 (the coil spring 104 is extended at this time). As shown by the white arrow in FIG. 3B, the toner conveying member 102 is pushed downward to contract the coil spring 104, and then the contact of the protrusion 103 with the protrusion 103 is released to restore the coil spring 104. Due to the force, the toner conveying member 102 returns upward as shown in FIG. 3C.

  However, at the initial stage of toner replenishment or the like, when loosening the toner inside, there is a situation where the non-circular rotating body 110 needs to be rotated in reverse as shown by the arrow in FIG. In such a reverse rotation, as shown by the white arrow in FIG. 3D, the toner conveying member 102 moves in the horizontal direction, and the toner conveying member 102 returns to the original horizontal position. Since there is a case where the toner does not return, the amplitude of the vertical movement (that is, the vibration in the vertical direction) is reduced, and there is a possibility that the toner conveying member 102 is clogged with toner.

  On the other hand, in the toner conveying device 40 according to the present embodiment, as described below, an urging force is applied to return to the original horizontal position, so that the amplitude of the vertical movement is not reduced, and the toner is conveyed to the toner. The member 41 is not clogged. Details of the toner transport device 40 according to the present embodiment will be described with reference to FIGS. 4A to 5 together. 4A and 4B are perspective views of the toner conveying device of FIG. 2, and FIG. 4B is a view as seen from the opposite direction to FIG. 4A. FIG. 4C is an exploded view of the toner conveying device of FIGS. 4A and 4B. FIG. 5 is a diagram showing details of the toner conveying device of FIG. Of course, the shape of the toner conveying device 40 illustrated here is not limited to this.

  The toner conveying device 40 includes a toner conveying member 41. The toner transport member 41 has a toner transport path through which toner is transported (that is, a pipe-shaped member), and is disposed so that the openings at both ends of the toner transport path face upward and downward. The As illustrated in FIG. 2 and the like, the toner conveying member 41 is exemplified as being disposed obliquely, but this is merely a consideration of the structure of the arrangement portion in the image forming apparatus A. The inside of the toner conveying member 41 serving as the toner conveying path is preferably a circular cavity, but the inner surface may be a smooth curved surface, that is, a smooth surface without unevenness in which toner particles can stay.

  In addition to the toner conveying member 41, the toner conveying device 40 includes a support member 42 and a driving mechanism which will be described later. The support member 42 is a member that supports the toner conveying member 41 so as to be movable in the vertical direction. The support member 42 exemplified here has a support plate part and a guide pipe part (pipe cover part) 42e on the upper side, and a transport pipe receiving part 44 on the lower side. Further, the intermediate portion of the support member 42 has, for example, a box shape as illustrated in FIG. 4A and the like.

  The pipe cover part 42 e guides the toner introduced from the toner insertion port of the attachment part for attaching the toner cartridge to the toner conveying member 41. Accordingly, the inner diameter of the lower end portion of the pipe cover portion 42 e is set so as to correspond to the inner diameter of the toner conveying member 41. As shown in FIG. 4C, the transport pipe receiving portion 44 has a discharge port that communicates with a toner discharge path (toner passage) 42 c at the lower end of the support member 42, and the lower end portion of the discharge port is connected to the developing device 2. The discharge port is provided with a slidable shutter. The shutter is urged by a coil spring that is an elastic member provided inside the conveyance pipe receiving portion 44, and the toner conveyance device 40 is developed by the developing device 2. When it is not attached, it is closed, and when it is attached, it is open.

  Further, the support member 42 preferably has deformable elastic members 42d and 42f having toner paths at connection portions with openings at both ends (upper and lower ends) of the toner transport member 41. In this case, the lower end portion of the pipe cover portion 42e is connected to the upper end portion of the toner conveying member 41 via the elastic member 42d, and the frame portion forming the toner discharge path 42c is the lower end of the toner conveying member 41 via the elastic member 42f. It will be connected to the part. As the elastic members 42d and 42f, for example, foamable elastic members are used as in the elastic member described in Patent Document 3.

  The elastic member 42d and the elastic member 42f can be deformed by applying an external force, and can return to the original shape when the external force is released. Accordingly, the toner conveying member 41 is connected to the pipe cover portion 42e on the toner cartridge mounting portion side via the elastic member 42d, and further connected to the conveying pipe receiving portion 44 via the elastic member 42f. It can move up and down between the cover part 42e and the transport pipe receiving part 44.

  In addition, a protrusion (projection piece) 41 a that is an operation protrusion is formed on the toner conveying member 41. The drive mechanism includes a non-circular rotating body 31 provided on the upper portion of the toner conveying member 41 and capable of contacting the protrusion 41a, and a coil spring (between the support member 42 and the toner conveying member 41). And a mechanism for moving the toner conveying member 41 in the vertical direction with respect to the support member 42.

  In the present embodiment, the non-circular rotating body 31 is assumed to be rotatable, that is, rotatable in both forward and reverse directions. Therefore, in the present embodiment, the driving mechanism is a mechanism that pushes the toner conveying member 41 downward during the forward rotation of the non-circular rotating body 31 and pushes the toner conveying member 41 laterally during the reverse rotation. The non-circular rotating body 31 may be a gear that has a plurality of convex portions 31a in the circumferential direction and has convex portions (operation wings) arranged at equal intervals, but is not limited thereto and may be any shape that functions as a cam. .

  As shown in FIG. 4B and the like, the coil spring 43 has one end attached to the toner conveying member 41 and the other end attached to the main body of the support member 42. More specifically, the back of the toner conveying member 41 is covered with a support member 42, and a locking portion for locking the coil spring 43 is formed on the back as illustrated in FIG. 4C. ing. The locking portion has a side wall 42 a slightly wider than the diameter of the coil spring 43 and a projection 42 b that points into one end of the coil spring 43. In addition, a protrusion 41 b for pointing the other end of the coil spring 43 is also formed on the outside of the toner conveying member 41.

  A rough portion of the vertical movement by the drive mechanism is as described briefly in FIG. 3A and the like. Specifically, in the toner conveying member 41, each convex portion 31 a slides on the end surface of the protruding portion 41 a by the rotation of the non-circular rotating body 31, and lifts the toner conveying member 41 against the urging force of the coil spring 43. Alternatively, the movement in the downward direction and the movement in which each convex portion 31a moves away from the end face of the protrusion 41a are sequentially repeated, so that the toner conveying member 41 is repeatedly moved in the vertical direction. As a result, the toner conveying member 41 can move in the vertical direction.

  Further, as illustrated in FIG. 5 and the like, the toner conveying member 41 has a tip for contacting the inner wall of the support member 42 when the toner conveying member 41 is moved by the driving mechanism on the outer peripheral side and near the center in the vertical direction. It is preferable to have a convex portion 41c. The toner conveying member 41 is supported and guided by a convex portion 41c having a small contact area on the inner wall of the support member 42, and is movable in the vertical direction. Needless to say, the present invention is not limited to this example, and a convex portion may be formed on the inner wall side of the support member 42 without providing the convex portion on the outer peripheral side of the toner conveying member 41.

  As a main feature of the present embodiment, the coil spring 43 is provided such that the expansion / contraction direction is oriented in a direction with a predetermined angle θ with respect to the vertical direction. As shown in FIG. 5, the predetermined angle θ is the direction of forward rotation on the protrusion 41 a side of the non-circular rotating body 31 with respect to the lower side of the coil spring 43 (referred to in FIG. 5). The angle is tilted to the left. In the present embodiment considering reverse rotation, the predetermined angle θ can be said to be an angle inclined in the direction opposite to the direction in which the toner conveying member 41 is pushed from the lateral direction with respect to the upper side of the coil spring 43.

  Thus, by arranging the coil spring 43 at the predetermined angle θ with respect to the vertical movement direction, the coil spring 43 can bias the toner conveying member 41 in the direction of pushing the toner conveying member 41 leftward in FIG. Therefore, unlike the example described with reference to FIGS. 3A to 3D, in the toner conveying device 40 illustrated in FIG. 5, even when it is necessary to rotate the non-circular rotating body 31 in the opposite direction, the vertical movement Thus, toner clogging can be prevented. In addition, the technique described in Patent Document 3 can be applied as appropriate, such as attaching a cylindrical sleeve as a toner loosening member to the lower end region of the inner wall constituting the toner conveyance path of the toner conveyance member 41.

(Second Embodiment)
The second embodiment of the present invention will be described with reference to FIG. 6 while focusing on the differences from the first embodiment, but various application examples described in the first embodiment can also be applied. . FIG. 6 is a schematic diagram illustrating a configuration example of the toner conveyance device according to the present embodiment.

  Since the toner conveying member only needs to have the openings at both ends facing upward and downward, as illustrated in FIG. 2 and the like, the toner conveying member 41 is illustrated in FIG. 6 even though it is not disposed obliquely. Like the toner conveying device 60, the toner conveying member 61 may be arranged in the vertical direction. Reference numerals 61a, 61b, and 61c are portions corresponding to the reference numerals 41a, 41b, and 41c, respectively.

  Also in this case, the predetermined angle θ is the direction of the positive rotation on the projection 61a side of the non-circular rotating body 31 with respect to the lower side of the coil spring 43, as in the first embodiment (FIG. 6). It is an angle inclined to the left).

(Third embodiment)
The third embodiment of the present invention will be described focusing on differences from the first and second embodiments, but various application examples described in the first and second embodiments can also be applied. In the first and second embodiments, the description has been made on the assumption that the non-circular rotating body can be reversely rotated. However, the present invention can be similarly applied to a configuration without reverse rotation. An example is briefly described.

  In the present embodiment, unlike the first and second embodiments, the non-circular rotating body 31 rotates only in one direction. Therefore, the drive mechanism moves the toner conveying member 41 downward when the non-circular rotating body 31 rotates. It becomes a mechanism to push on. Also in this case, as shown in FIG. 3A, when a gap (play) 105 is provided in the horizontal direction between the toner conveying member 102 and the support member 101, the operation that causes the toner conveying member 102 to escape in the horizontal direction. As a result, there is a possibility that the toner conveying member 102 may be clogged as a result.

  On the other hand, in the present embodiment, as illustrated in FIG. 5 (FIG. 6), the coil spring 43 is provided with the predetermined angle θ with respect to the vertical movement direction so that the coil spring 43 is projected. Via 41b (61b), the toner conveying member 41 is urged in the direction of pushing leftward in FIG. 5 (FIG. 6). Accordingly, in the configuration in which a gap similar to the gap 105 is provided between the convex portion 41c (61c) and the inner wall of the support member 42, the protrusion 41a is flipped to the right by the one-way rotation by the non-circular rotating body 31. Even in such a situation, it can be returned to the left, and the amplitude of the vertical movement is not reduced.

  When the non-circular rotating body 31 rotates in the direction indicated by the arrows in FIGS. 5 and 6, the vertical motion amplitude tends to increase conversely in the scene where the protrusion 41 a is flipped to the left. There is no problem because there is.

A: Image forming apparatus, 2 (2a to 2d): Developing device, 20 (20a to 20d): Toner cartridge, 30: Toner cartridge drive unit, 31: Non-circular rotating body, 31a: Projection, 40 (40a to 40d) ), 60... Toner transport device, 41, 61... Toner transport member, 41 a, 61 a... Upper protrusion, 41 b, 61 b ... Protrusion, 41 c, 61 c ... Projection, 42 ... Support member, 42 a. Projection part of support member, 42c... Toner discharge path, 42d and 42f... Elastic member, 42e ... pipe cover part, 43 ... coil spring, 44 ... transport pipe receiving part.

Claims (6)

A toner transport device comprising a toner transport member having a toner transport path through which toner is transported and having openings at both ends of the toner transport path facing upward and downward;
A support member that supports the toner conveying member so as to be movable in the vertical direction;
The toner conveying member is supported by the non-circular rotating body capable of contacting a protrusion provided on the toner conveying member, and a coil spring disposed between the supporting member and the toner conveying member. A drive mechanism that moves in the vertical direction with respect to
With
The coil spring is provided such that the expansion / contraction direction is oriented in a direction with a predetermined angle with respect to the vertical direction,
The toner conveying apparatus according to claim 1, wherein the predetermined angle is an angle in which the upper side of the coil spring is inclined with respect to the lower side in the direction of forward rotation on the protruding portion side of the non-circular rotating body. The non-circular rotating body is rotatable in both forward and reverse directions,
2. The mechanism according to claim 1, wherein the driving mechanism is a mechanism that pushes the toner conveying member downward when the non-circular rotating body rotates forward and pushes the toner conveying member laterally when rotating reversely. Toner transport device.   3. The toner transport device according to claim 1, wherein the support member includes a deformable elastic member having a toner passage at a connection portion between the opening portions at both ends of the toner transport member.   The toner conveying member has a convex portion having a tip for contacting the inner wall of the support member when the toner conveying member is moved by the driving mechanism, on the outer peripheral side and in the vicinity of the center in the vertical direction. The toner conveying device according to any one of claims 1 to 3.   5. The toner transport device according to claim 1, a toner replenishing device mounted above the toner transport device, and mounted below the toner transport device, from the toner replenishing device to the toner. A toner supply device comprising: a developing device that receives toner replenishment via a conveying device; An image forming apparatus comprising the toner supply device according to claim 5.

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